Using the normal distribution, it is found that 495 readings fall within 5.15cm of the mean value.
In a normal distribution with mean and standard deviation
, the z-score of a measure X is given by:
- It measures how many standard deviations the measure is from the mean.
- After finding the z-score, we look at the z-score table and find the p-value associated with this z-score, which is the percentile of X.
In this problem:
- Mean of 5m, hence
.
- Standard deviation of 2 cm, hence
To find the proportion of readings that fall within 5.15cm of the mean value, first we need to find the following z-score:
The proportion is P(|z| < 2.575), which is the p-value of z = 2.575 subtracted by the p-value of z = -2.575.
Looking at the z-table, z = -2.575 has a p-value of 0.005, and z = 2.575 has a p-value of 0.995.
0.995 - 0.05 = 0.99
Out of 500 measurements:
(0.99)500 = 495
495 readings fall within 5.15cm of the mean value.
A similar problem is given at brainly.com/question/24663213